A storage system typically comprises one or more storage devices into which information may be entered, and from which information may be obtained, as desired. The storage system includes an operating system that functionally organizes the system by, inter alia, invoking storage operations in support of a storage service implemented by the system. The storage system generally provides its storage services through the execution of software modules, such as processes. The storage system may be implemented in accordance with a variety of storage architectures including, but not limited to, a network-attached storage environment, a storage area network and a disk assembly directly attached to a client or host computer. The storage devices are typically disk drives organized as a disk array, wherein the term “disk” commonly describes a self-contained rotating magnetic media storage device. The term disk in this context is synonymous with hard disk drive (HDD) or direct access storage device (DASD).
The storage system may be further configured to operate according to a client/server model of information delivery to thereby allow many clients to access information stored on the system. In this model, the storage system may be embodied as file server executing an operating system, such as the Microsoft® Windows™ operating system (hereinafter “Windows operating system”). Furthermore, the client may comprise an application executing on an operating system of a computer that “connects” to the server over a computer network, such as a point-to-point link, shared local area network, wide area network, or virtual private network implemented over a public network, such as the Internet. Each client may request the services of the server by issuing storage access protocol messages (in the form of packets) to the server over the network. By supporting a plurality of storage (e.g., file-based) access protocols, such as the conventional Common Internet File System (CIFS) and the Network File System (NFS) protocols, the utility of the server is enhanced.
To facilitate client access to the information stored on the server, the Windows operating system typically exports units of storage, e.g., (CIFS) shares. As used herein, a share is equivalent to a mount point or shared storage resource, such as a folder or directory that stores information about files or other directories served by the file server. A Windows client may access information in the directory by mounting the share and issuing a CIFS protocol access request that specifies a uniform naming convention (UNC) path to the share. The UNC path or pathname is an aspect of a Windows networking environment that defines a way for a client to refer to a unit of storage on a server. The UNC pathname is prefixed with the string \\ to indicate resource names on a network. For example, a UNC pathname may comprise a server name, a share (directory) name and a path descriptor that collectively reference a unit of storage or share. Thus, in order to access the share, the client typically requires knowledge of the specific physical location (i.e., the identity) of the server exporting the share.
Instead of requiring the client to provide the specific identity of the file server exporting the share, it is desirable to only require a logical pathname to the share. That is, it is desirable to provide the client with a globally unique pathname to the share without reference to the file server. The conventional Distributed File System (DFS) namespace service provides such a solution in a Windows environment through the creation of a namespace that removes the specificity of server identity. DFS is well-known and described in DCE 1.2.2 DFS Administration Guide and Reference, 1997, which is hereby incorporated by reference. As used herein, a namespace is a view of shared storage resources (such as shares) from the perspective of a client. The DFS namespace service is generally implemented using one or more DFS servers and distributed components in a network.
Using the DFS service, it is possible to create a unique pathname (in the form of a UNC pathname) for a storage resource that a DFS server translates to an actual location of the resource (share) in the network. However, in addition to the DFS namespace provided by the Windows operating system, there are many other namespace services provided by various operating system platforms, including the NFS namespace provided by the conventional Unix® operating system. Each service constructs a namespace to facilitate management of information using a layer of indirection between a file server and client accessing a shared storage resource (share) on the server. For example, a share may be connected or “linked” to a link point (link in DFS terminology or a mount point in NFS terminology) to hide the machine specific reference to the share. By referencing the link point, the client can automatically access information on the storage resource of the specific machine. This allows an administrator (user) to store the information on any server in the network by merely providing a reference to the information (or share). However, these namespaces are typically services created on heterogeneous server platforms, which leads to incompatibility and non-interoperability with respect to management of the namespaces by the user. For example, the DFS namespace service is generally limited to Windows-based operating system platforms, whereas the NFS namespace service is generally limited to Unix-based operating system platforms.
The Virtual File Manager (VFM™) developed by NuView, Inc. and available from Network Appliance, Inc., (“NetApp”) provides a namespace service that supports various protocols operating on various file server platforms, such as NetApp filers and DFS servers. The VFM namespace service is well-known and described in VFM™ (Virtual File Manager) Reference Guide, Version 40, 2001-2003, and VFM™ (Virtual File Manager) Getting Started Guide, Version 4.0, 2001-2003.
A large-scale storage system environment may include many (e.g., hundreds of) storage systems hosting resources embodied as, e.g., storage and namespace objects. As used herein, namespace objects include namespaces, link points and shares, whereas storage objects include servers, files and disks. In order to perform namespace and storage management in such a large-scale storage system environment, it is desirable to provide a graphical user interface (GUI) of a management console that enables users to manage multiple storage system resources efficiently, e.g., as one or more groups of managed objects.
In addition, it is desirable to provide a GUI having an architecture that produces GUI components, such as dialog boxes (“dialogs”) and wizards, which can be reused with various applications executing on the management console. As used herein, a dialog is a movable window that appears on a computer screen of the NSM console and that provides status, as well as available options for an application executing on the console. A wizard is an interactive utility that may be implemented as a sequence of dialogs adapted to guide a user through an operation flow, inputting information as required by the flow.
A simple operation flow as embodied in a wizard typically comprises a fixed number of pre-defined steps organized in a serial or linear manner. However, such a linear flow of operations is inflexible and may increase the number of steps the user must follow to initiate a task or action. As a result, it is further desirable to identify dependencies in the operation flow and exploit those dependencies to provide an optimized flow of operations that limits the number of steps that the user need follow. Moreover, it is desirable to provide a wizard that allows a user to make intelligent choices towards successful completion of a desired action using the optimized operation flow.